"I do my intellectual work inside myself, and once I am with my fellow creatures it is more or less a matter of indifference to me whether or not they are intelligent as long as they are kind, sincere, etc."

Next Quote

In your letter you apply the word imponderable to a molecule. Don't do that again. It may also be worth knowing that the aether cannot be molecular. If it were, it would be a gas, and a pint of it would have the same properties as regards heat, etc., as a pint of air, except that it would not be so heavy.

— James Clerk Maxwell