The Parthenon, along with Cheops’s pyramid, Wren’s churches and Mansard’s palaces —ranks as an architectural archetype(A)/prototype (B).

The builders of the Parthenon were steeped (A)/steered (B) by tradition, yet free to experiment.

They worked to (A)/for (B) extreme precision, yet the final result was anything but rigid.

Knowing that long horizontal lines appear to sag, even though they are absolutely straight, horizontal elements were deliberately curved and the vertical columns “fattened” in the middle to compensate (A)/accommodate (B) for the vagaries of the human eye.

European scholars rightly (A)/wrongly (B) viewed all great powers in history as global powers.

However, the unipolar world of the British and American empires was a historical milestone (A)/ aberration(B).

For most, global moments were short-lived. Even so (A)/At best (B), they were continental powers.

Multipolarity or polycentric dispersal (A)/dispensing (B) of power and prosperity defines the normal state of the world.

The loss of the presidency in 2008 thrust the Republican party into a period of intense ideological turmoil, which strengthened (A)/upended (B) the moral consensus.

On some issues, including health care and climate change, the tea-party revolution drove Republicans further to the right, creating the new orthodoxy (A)/schism (B).

But on other issues, such as foreign policy and gay marriage, differences that had been papered (A)/debated(B) over suddenly broke free.

The big loss in 2008 allowed a cabal(A)/faction(B) of the Republican elite to switch sides.

Magna Carta was an ephemeral (A)/abiding (B) agreement between 25 nobles and King John, setting out certain baronial rights in England in 1215.

The original agreement was in effect only for a short time after the 15 June sealing, after (A)/ before(B) being voided by Pope Innocent III.

Ostensibly (A)/ Nevertheless (B), the Magna Carta has rocked the Western world for centuries, setting off tremors that still reverberate in the US Bill of Rights about individual liberties and the concept of speaking truth to power.

Until (A)/But while (B) the vellum sheets of Magna Carta are preserved, there is a real debate in the world over whether or not the freedoms that have their beginnings in the charter might well be on the decline.

Just by maintaining green pockets or isolated reserves humans cannot forever maintain the ecological process and functions that are at the core of the ecosystem but (A)/ and thus (B) forestall environmental disasters.

It is virtually impossible to enclose nature within any boundaries. Nature spans rather than (A)/as well as (B) spills over borders.

It is only by inquiring (A)/ enquiring (B) into ecology, economics, and culture and by asking how they are interwoven that now we can move on ahead.

Nevertheless (A)/After all (B), the borders within which we have tried to sequester nature against the siege of human demographic and economic growth are important symbols for they remind us of what we would like to secure and against what.