1 Corinthians 1:28

and the base things of the world, and the things that are despised, did God choose, yea and the things that are not, that he might bring to nought the things that are:

'things' -apparently refer to groups of people, categories of people. Categories that the world looks down upon. The things which the world "considers" foolish. The things in the gospel (the cross,. suffering Messiah) matches the type of people that often accept it, i.e. the world despises both.

'What God did in the cross and in calling "lowly" Corinthians not only exhibits his own character, that he is gracious, but also illustrates that he is not beholden to the world..Thus he is not accountable to the "wise" of this world.' (Fee p. 83)

'put to shame' -eternal shame is reserved for those that reject the gospel.

'base' -36. agenes ag-en-ace'; from. (as negative particle) and 1085; properly, without kin, i.e. (of unknown descent, and by implication) ignoble: -base things. 'Of no family, the reverse of noble' (Vincent p. 194)

'that are despised' -'Not merely despised, but expressly branded with contempt' (Vincent p. 194) 'God has chosen what the world holds base and contemptible' (Knox)

'the things that are not' -'and what it thinks does not exist' (Wms); 'things that to it are unreal' (TCNT) This could also refer to people that the world considers to be nobodies. (Matthew 11:25)