Plutarch 
Plutarch’s Morals 

Some of the things that grow on the earth are in their nature wild and barren and injurious to the growth of seeds and plants, yet those who till the ground consider them indications not of a bad soil but of a rich and fat one;637 so also there are passions of the soul that are not good, yet are as it were offshoots of a good disposition, and one likely to improve with good advice. Among these I class shyness, no bad sign in itself, though it affords occasion to vice. For the modest oftentimes plunge into the same excesses as the shameless, but then they are pained and grieved at them, and not pleased like the others. For the shameless person is quite apathetic at what is disgraceful, while the modest person is easily affected even at the very appearance of it. Shyness is in fact an excess of modesty. And thus it is called shamefacedness, because the face exhibits the changes of the mind. For as dejection is defined to be the grief that makes people look on the ground, so shamefacedness is that shyness that cannot look people in the face.