The phrase "and he discerned" is correct and usable in written English.
It can be used when describing a moment of realization or understanding, often in a narrative context.
Example: "As he walked through the crowded market, he discerned the subtle differences in the vendors' offerings."
Alternatives: "and he perceived" or "and he recognized".
Piero could amuse his fellow-citizens with his knack for seeing things, as when he paused in the street, Vasari writes, "to contemplate a wall at which sick people had for ages been aiming their spittle" and described how he discerned there "battles between horsemen, and the most fantastic cities, and the most extensive landscapes ever seen".
In an essay called "Fiction and Reality in Latin America," he discerned even in the conquest of the Incas a message more anti-dictatorial than anti-imperialist: "The vertical and totalitarian structure of the Tahuantinsuyu was, without doubt, more of a threat to its survival than all the conquistadors' firearms and iron weapons".
He discerned, he said, that "music and poetry have a common domain, from which they draw inspiration and in which they operate: the landscape of the soul".
He thought that he discerned a LoBagola pattern.
In this hopeless situation, he discerned an advantage.
Its "invincible obscurity" was distasteful to More's rationalist sensibilities, and he also discerned monistic materialism in it, and even pantheism.
Wilson reveals that the new caste of wealthy Melbourne gold-diggers who emerged in the 1850s were known as the "hairystocracy", and beneath their bristles he discerns the face of a new, distinctly Australian form of libertarianism.
He discerns destruction and the dark undercurrents of European history all around.
Looking into the eyes of a bear that comes close to Treadwell's camera, he discerns cruelty and mercilessness rather than hunger.
"He can sit there listening to 20 sources of sound, and he can discern from all that noise the newsworthy items," Mr. Gessman said.
