That there is no such thing as what philosophers call material substance, I am seriously persuaded: but if I were made to see any thing absurd or ske… - George Berkeley

Seeing therefore they are both [heat and pain] immediately perceived at the same time, and the fire affects you only with one simple, or uncompounded idea, it follows that this same simple idea is both the intense heat immediately perceived, and the pain;and consequently, that the intense heat immediately perceived, is nothing distinct from a particular sort of pain.

Since therefore, as well those degrees of heat that are not painful, as those that are, can exist in a thinking substance; may we not conclude that external bodies are absolutely incapable of any degree of heat whatsoever?

I entirely agree with you, as to the ill tendency of the affected doubts of some philosophers, and fantastical conceit of others. I am even so far gone of late in this way of think, that I have quitted several of the sublime notions I had got in their schools for vulgar opinions. And I give it you on my word, since this revolt from metaphysical notions to the plain dictates of nature and common sense, I find my understanding strangely enlightened, so that I can now easily comprehend a great many thing which before were all mystery and riddle.