positive feedback
[De].
A system's response to external stimuli leading to further changes that serve to reinforce the initial response, thereby creating and accelerating a cause and effect loop.
positive lynchet
[Co].
The build-up of soil and sediment on the up-slope side of a wall or fenceline running across a hillside. Because the wall or fence serves to halt the down-slope movement of material, the accumulation may eventually bury it. Such a build-up is further exaggerated by the fact that on the down-slope side of the developing lynchet there is likely to be a loss of material from the soil profile. This is known as the
negative lynchet
. Ultimately, the effect of lyncheting is to create a series of flat steps or cultivation terraces up the side of a hill.
positivism
[Th].
The school of philosophy developed by Auguste Comte in the 19th century stating that reality can be apprehended objectively and that data (facts) should be separated from the theories that explain them (interpretations). Following this logic, explanation in the social sciences can and should be as objective and empirical as in the natural sciences, and any interpretative statements made should be testable in some way. This finds expression in archaeology as
PROCESSUAL
or
NEW ARCHAEOLOGY
where an essentially
EMPIRICIST
approach is adopted. Here the aim is to explain observed phenomena with reference to a set of general relationships rather than a series of laws, as might be expected in the natural sciences. Archaeology places an emphasis on empirical data as the primary means of testing the explanations offered because such data are regarded as objectively recovered through archaeological fieldwork. Quantitative and mathematical techniques are liberally applied within positivist archaeology. In seeking explanations, positivist archaeology differs very considerably from
POST-PROCESSUAL ARCHAEOLOGY
which attempts understanding.
post and panel
[De].
A term applied to the construction of the kerbs in some classes of
MEGALITHIC TOMBS
in which upright stones (
PERISTALITHS
) are set at intervals with blocks of dry-stone walling between.
post circle
[MC].