Key Arguments

• Locke contrasts the passive reception of simple ideas with the mind’s active role in forming others: 'the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed.'
• He identifies three principal acts by which the mind exerts power over its simple ideas: '(I) Combining several simple ideas into one compound one; and thus all complex ideas are made. (II) The second is bringing two ideas, whether simple or complex, together, and setting them by one another, so as to take a view of them at once, without uniting them into one; by which way it gets all its ideas of relations. (III) The third is separating them from all other ideas that accompany them in their real existence: this is called abstraction: and thus all its general ideas are made.'
• He explicitly defines complex ideas as products of combination: 'Ideas thus made up of several simple ones put together, I call complex; — such as are beauty, gratitude, a man, an army, the universe.'
• He insists that, in these operations, the mind can work not only with combinations found in external objects but also with combinations it itself makes: 'As simple ideas are observed to exist in several combinations united together, so the mind has a power to consider several of them united together as one idea; and that not only as they are united in external objects, but as itself has joined them together.'

Source Quotes

Made by the mind out of simple ones. We have hitherto considered those ideas, in the reception whereof the mind is only passive, which are those simple ones received from sensation and reflection before mentioned, whereof the mind cannot make one to itself, nor have any idea which does not wholly consist of them. But as the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed.

We have hitherto considered those ideas, in the reception whereof the mind is only passive, which are those simple ones received from sensation and reflection before mentioned, whereof the mind cannot make one to itself, nor have any idea which does not wholly consist of them. But as the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed. The acts of the mind, wherein it exerts its power over its simple ideas, are chiefly these three: (I) Combining several simple ideas into one compound one; and thus all complex ideas are made.

But as the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed. The acts of the mind, wherein it exerts its power over its simple ideas, are chiefly these three: (I) Combining several simple ideas into one compound one; and thus all complex ideas are made. (II) The second is bringing two ideas, whether simple or complex, together, and setting them by one another, so as to take a view of them at once, without uniting them into one; by which way it gets all its ideas of relations.

As simple ideas are observed to exist in several combinations united together, so the mind has a power to consider several of them united together as one idea; and that not only as they are united in external objects, but as itself has joined them together. Ideas thus made up of several simple ones put together, I call complex; — such as are beauty, gratitude, a man, an army, the universe; which, though complicated of various simple ideas, or complex ideas made up of simple ones, yet are, when the mind pleases, considered each by itself, as one entire thing, and signified by one name. 2.

I shall here begin with the first of these in the consideration of complex ideas, and come to the other two in their due places. As simple ideas are observed to exist in several combinations united together, so the mind has a power to consider several of them united together as one idea; and that not only as they are united in external objects, but as itself has joined them together. Ideas thus made up of several simple ones put together, I call complex; — such as are beauty, gratitude, a man, an army, the universe; which, though complicated of various simple ideas, or complex ideas made up of simple ones, yet are, when the mind pleases, considered each by itself, as one entire thing, and signified by one name.

Key Concepts

• We have hitherto considered those ideas, in the reception whereof the mind is only passive, which are those simple ones received from sensation and reflection before mentioned, whereof the mind cannot make one to itself, nor have any idea which does not wholly consist of them.
• as the mind is wholly passive in the reception of all its simple ideas, so it exerts several acts of its own, whereby out of its simple ideas, as the materials and foundations of the rest, the others are framed.
• The acts of the mind, wherein it exerts its power over its simple ideas, are chiefly these three: (I) Combining several simple ideas into one compound one; and thus all complex ideas are made.
• Ideas thus made up of several simple ones put together, I call complex; — such as are beauty, gratitude, a man, an army, the universe;
• as simple ideas are observed to exist in several combinations united together, so the mind has a power to consider several of them united together as one idea; and that not only as they are united in external objects, but as itself has joined them together.

Context

Book II, chapter XII, section 1, where Locke opens his discussion of complex ideas by contrasting passive reception of simple ideas with active mental operations that generate complex, relational, and abstract ideas.