Who thinks we have lots of ideas all the time, only a few of which we are actually conscious of?

The notion that there may be mental-goings on of which we may be unconscious reaches clear articulation in Freud (1856-1939) but you can argue that it is strongly hinted at in Wordsworth, writing within the Romantic Movement at the beginning of the previous century, when he is describing childhood experiences and the residue they leave. Descartes wrenched 'idea' from its Scholastic moorings, and Locke gave a clear definition of the term, absolutely central to the new theory of the human being: an idea is whatever is before the mind when a person thinks. So for Locke (and for Berkeley, who followed him in this as in the great bulk of Locke's tenets) you can't have an idea that you are not aware of. This reminds us that 'idea' has changed its meaning quite a bit ...