Philosopher David Hume on the Academic or Sceptical Philosophy Summary

SECTION XII: on the Academic or Sceptical Philosophy

116-23. There are not to be found more philosophical reasonings on any subject than those refuting the Atheists by proving the existence of a Deity. And yet most religious philosophers believe that no one can be so blind as to be an atheist. At least the knights of old who sought to remove dragons had no doubt in their existence.

The Sceptic is another enemy of religion who provokes the indignation of all divines. However, a total sceptic is not to be found because everyone has opinions and principles by which he thinks and lives.

What is a sceptic? There are several species --

Universal doubt : (that of Descartes and others) of all former opinions, principles and faculties. But such doubt is plainly impossible and incurable. Reasoning can never lead any conviction. However, a more moderate form of this species of scepticism is necessary for the study of philosophy by bringing impartiality to our judgment and by removing prejudice. We must begin with clear and self-evident principles, advance carefully, review regularly, and examine consequences accurately. This is the only method for reaching truth.

Consequential doubt : to find through science and enquiry the fallaciousness of the mind and the senses questioning even the maxims of common life. Of course our sense organs can be fallacious by providing the crooked appearance of an oar in water, the misleading perceptions of a view from a distance, and the double image of a pressed eye. Obviously the sense alone cannot be depended upon and our senses require reason as a corrective. The image made by the senses is not the external object and can merely represent it. As we move from a table it gets smaller, but this is from our perspective; the table itself is unaffected. This is a dictate of reason: our images are copies of an independently existing object that does not change with the perceptions of it.

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But how can it be proved that perceptions of the mind are caused by external objects and not by the mind itself as in a dream or in madness. Here experience is silent, for the mind only receives perceptions and cannot gain experience of their connection with objects.

To take recourse to a Supreme Being is to make our senses infallible, for such a Being would not deceive. Further, to call into question an external world in this way would reject the possibility of proving the existence of such a Being.

Qualities such as hard, soft, hot, cold, black, and white are acknowledged as secondary qualities existing not in an object but in the mind. But this must also follow with the supposed primary qualities of extension and solidity. Extension is acquired from the senses of sight and feeling. If all qualities perceived by the senses are in the mind, then extension is to be found there. It must be concluded that the ideas of these primary qualities are attained by abstraction, but this is an unintelligible, absurd opinion. Try to conceive of an abstract triangle that is neither Isosceles nor Scalene and of no particular size or shape, and you find that it cannot be done. Remove from matter its primary and secondary qualities and you annihilate it. Even all sceptics would have to agree.

Part II

124. Sceptics attempt to destroy reason by argument. But even scepticism must be driven to the use of reason. Thus sceptics themselves must become sceptical of their scepticism.

Sceptical objections to moral evidence or to reasonings concerning matters of fact are derived from the natural weakness of human understanding, including the existence of conflicting opinions and our own changing judgments over the years. But because we cannot avoid making and reacting to decisions reached moment by moment, later experience and argument is irrelevant and not a reason for total scepticism. Our actions subvert extreme scepticism. As soon as sceptical philosophers leave the shade of their cloisters and enter the world of real objects and sentiments, their principles vanish like smoke. Where they had grounds for their scepticism is that all reasoning concerning cause and effect concludes that two objects can be experienced as conjoined together but not connected. For we cannot conclude that what has been conjoined together in the past will be in the future, and that this conjoining is actually a connection. Repetitions in relationships in the past guarantee nothing for the future. This seems to destroy conviction but does not remove the need for action.

The main objection to excessive scepticism is this: nothing durable and good can ever result from it. If we ask the Sceptic, &What are you talking about, what is your intention?& -- he is silent. A Copernician and a Ptolemaic have different systems of astronomy, but they are at one in seeking conviction. A Stoic and Epicurean have principles which effect behaviour. But a Pyrrhonian, an extreme sceptic, expects no influence on the mind. Indeed, he must acknowledge, though is unlikely to admit it, that if his principles were universally accepted, all activity would cease and the world would perish. The argument against the Pyrrhonian principle of total scepticism is that one must act and reason and believe if one is to live.

Part III

130. But Pyrrhonism, or excessive scepticism, if corrected by common sense and reflection, can help yield a durable and useful scepticism. Mankind is often too dogmatic and unwilling to consider more than one side of an issue. All need to become aware of weaknesses in human understanding and be more modest and less prejudicial against those who differ. A small tincture of Pyrrhonism might help the intellectually arrogant to understand that any advantage -- if any -- they may have over their fellows is little when contrasted with the confusion inherent in human nature. A degree of doubt must accompany every decision.

Pyrrhonian doubt should also warn mankind to limit enquiries to within the narrow capacity of human understanding. Imagination and speculation can run out of control, influencing incorrect judgments by not keeping enquiry to common life and within the confines of experience. Speculation is not the task of the philosopher and belongs, in any case, to the embellishments of poets, priests and politicians. The situation of nature before the origin of the world and beyond to eternity is out with the remit of the philosopher.

What is within the circle of appropriate investigation for philosophical enquiry? Demonstration by the abstract sciences should be limited to quantity and number. Reasoning beyond this boundary is sophistry. All other enquiries regard matters of fact and existence and are incapable of demonstration. It is just as conceivable that something does not exist as that it does. Both ideas are clear and distinct. Existence of any object can only be proven by arguments, founded on experience, from its cause to its effect. Arguments based upon à priori reasoning could conclude that anything could be able to produce anything else. We could reason that a falling pebble could extinguish the sun or that a person's wish could control the planets. Experience alone teaches the relationship of cause and effect. And this also applies to moral reasoning which concerns most of human knowledge and is the source of all human action and behaviour.

The sciences concerned with causes and effects of general facts include politics, natural philosophy, physics and chemistry.

Theology has a foundation in reason only as far as it is supported by experience. Its best foundation is faith and divine revelation.

Morality is not something to be understood but to be evaluated by taste and sentiment. Beauty is a feeling more than a perception. And if we reason concerning morality to set a standard, we must evaluate the general taste of mankind or seek another fact as the object of our reasoning and enquiry.

If we hold a book -- whether of divinity or metaphysics or whatever -- we should ask:

Does it contain any abstract reasoning concerning quantity or number?


Does it contain any reasoning based on experience concerning matter of fact and existence?


Then commit it to the flames for it can contain nothing but sophistry and illusion.

This argument comes from Dr. Berkeley and most of the writings of that ingenious author form the best lessons of scepticism to be found anywhere. Yet he professes in a title page (and truthfully) to have written against the atheists and free-thinkers. All his arguments are sceptical in that they admit of no answer and produce no conviction.

This paradox and contradiction can only be avoided if there are no abstract or general ideas but only particular ones attached to a general term. Thus the term &Horse& brings to mind a creature of a particular shape, size and colour, and variances can be easily recalled afterwards; but we reason as if they, too, were present in our mind. The same is true with the term &Number& or the idea of quantity. Think of one number at a time, and you will conclude that &Number& cannot be infinitely divisible.

Philosopher David Hume on the Academic or Sceptical Philosophy Summary

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