Qui observat ventum non seminat

Risk 

Qui observat ventum non seminat; et qui considerat nubes numquam metet. Ecl 11:4

Rashi says:

And he who looks to the clouds. He observes the clouds, and when he sees them darkening, he is afraid to harvest on account of the rains; he will never harvest because he is always fearful [of the rains].

 

Utility Theory and wealth management:

mane semina sementem tuam et vespere ne cesset manus tua quia nescis quid magis oriatur hoc an illud et si utrumque simul melius erit. Ecl. 11:6