The logical order of God's decrees is the study in Calvinist theology of the logical order (in God's mind, before Creation) of the decree to ordain or allow the fall of man in relation to his decree to save some sinners (election) and condemn the others (reprobation). Several opposing positions have been proposed, all of which have names with the Latin root lapsus meaning fall.
Supralapsarianism (also called antelapsarianism, pre-lapsarian or prelapsarian) is the view that God's decrees of election and reprobation logically preceded the decree of the fall while infralapsarianism (also called postlapsarianism and sublapsarianism) asserts that God's decrees of election and reprobation logically succeeded the decree of the fall. The words can also be used in connection with other topics, e.g. supra- and infralapsarian christology. The difference between the two views are minute; supralapsarianism, by virtue of its belief that God creates the elect and reprobate, is a suggestion or provides an inference that at some level, God is the author of sin (because he creates sinners to condemnation). Infralapsarianism teaches that all men are sinful by nature (due to The Fall), are thereby condemned through our own sin (freewill), and that God had foreknowledge of whom he would rescue from condemnation. The infralapsarianist view follows Ephesians 1:4-6, "... even as he chose us in him before the foundation of the world, that we should be holy and blameless before him. In love he predestined us for adoption to himself as sons through Jesus Christ, according to the purpose of his will, to the praise of his glorious grace, with which he has blessed us in the Beloved" (ESV). That is, some are chosen to be elect (foreknowledge) but not created elect.
Many Calvinists reject both lapsarian views for various reasons. Herman Bavinck rejected both because he sees the entire system of God's plan of salvation as organic with each part mutually dependent and determinative, rather than some parts "causing" others. Other Calvinists (and many non-Calvinists) reject the lapsarian views because they perceive any particular ordering of the decrees as unnecessary and presumptive speculation. Critics of lapsarianism often argue that it is impossible to conceive of a temporal process by which God, in eternity, issued decrees, and it is impossible to know the mind of God without direct, scriptural documentation.