The first objection is, that the universal which the system of Thales sets forth is a mere sensible universal. This is obvious from the consideration that, let us form what conception of water we may, we still think of it under some form of sensible representation. It is originally made known by the senses; and however delicate and subtle the form may be in which we endeavour to construe moisture to our minds, it still retains, in our conception, to a greater or less degree, the form under which we originally apprehended it. In other words, water or moisture is, in the first instance, an object of sense, a sensible presentation; and when we imagine it, or construe it to our minds, in the second instance, it is always a sensible representation.
In regard to the second ground of objection, I shall merely remark that water, the universal principle of all things according to Thales, being a sensible universal, is consequently not a necessary truth, not a truth for all intelligence, but only for those who are endowed with senses similar to ours. And consequently this system must be set aside as insufficient, inasmuch as it does not meet the requisitions of philosophy, philosophy being, according to our definition, that science which aims at the attainment of absolute truth, that is, of truth as it exists, not for some, but for all intelligence.
